Name:	fcel_CashCovenantMinimumRequiredPercentageOfUnrestrictedCashBalanceOnOutstandingLoanBalanceAndAccountsPayable
Namespace Prefix:	fcel_
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Period Type:	instant

Debt instrument, amendment description.

No definition available.

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Loan Advance

No definition available.

Name:	fcel_LoanAdvance
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Minimum required unrestricted cash balance under control agreement.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Term of loan.

No definition available.

Name:	fcel_TermOfLoan
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Period Type:	duration

The total of collateralized agreements including securities purchased under agreements to resell (repos), borrowed securities, and secured demand notes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(2)(i)(A))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 05
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=64836671&loc=d3e93640-111703

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The average effective interest rate during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration

Contractual interest rate for funds borrowed, under the debt agreement.

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Data Type:	num:percentItemType
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Period Type:	instant

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Period Type:	duration

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Period Type:	duration

Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Current portion of the total carrying amount as of the balance sheet date due within one year or the operating cycle, if longer, on all notes payable to banks paid on an installment with long term maturities. This can include the amount of any loans from the applicant firm. This does not, however, include any mortgage balances.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Other deductions and charges as defined.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

No definition available.

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_DebtInstrumentAxis=fcel_ConnecticutDevelopmentAuthorityNoteMember
Namespace Prefix:
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Name:	us-gaap_DebtInstrumentAxis=fcel_ConnecticutGreenBankNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=fcel_PNCEnergyCapitalLLCMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=fcel_ConnecticutDepartmentOfEconomicCommunityDevelopmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=fcel_StateOfConnecticutMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=fcel_HerculesCapitalIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesCPreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=fcel_NewBritainRenewableEnergyTermLoanMember
Namespace Prefix:
Data Type:	na
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